Question 11. Given the data below, find k.

Question

Given the data below for the reaction, 2 A + 2 B + 4 C => D + E + 3 F, the reaction is [a] order in A, [b] order in B, [c] order in C and [d] order overall.

Experiment	Initial conc of A, mol/L	Initial conc of B, mol/L	Initial conc of C, mol/L	Initial rate, mol/L.s
1	0.1	0.2	0.4	2 x 10-3
2	0.2	0.2	0.4	8 x 10-3
3	0.3	0.4	0.4	3.6 x 10-2
4	0.4	0.6	0.2	9.6 x 10-2

I found the order for A and B. I can't find the order for C. Whenever I plug numbers in, it doesn't give a correct answer to determine order. Why/how is C zero order?

Answers:

Second order in A

First order in B

Zero order in C

Third order overall

Answer 1

Since you found order for A and B, I'll just abbreviate my approach to see if I get the same answers as you.

1 vs. 2: second order in A

1 vs. 3: first order in B

Now, for C, I will compare 2 vs. 4: (2)²(3)¹(0.5)ⁿ = 12 and n = 0

So it is zero order in C

Overall is 2 + 1 + 0 = third order overall